In general drilling vessels are provided with tools and hang of clamps, such as riser spiders and slips, for working on, assembling, disassembling and supporting tubular strings in the firing line of the drilling tower. The tools and hang of clamps are typically designed to work with a tubulars having a specific diameter. When tubulars of a different diameter are to be handled, the tools and of clamps are often replaced with tools and clamps that fit the diameter of the other tubulars. Changing of clamps and tools in the firing line costs time.